Display, display system, image projection system, and movable object

Abstract

Provided is a head-up display including a liquid-crystal panel including a display screen, a Fresnel lens which is on an opposite side of the liquid-crystal panel from the display screen, a light-diffusion member between the liquid-crystal panel and the Fresnel lens, a backlight emitting light toward the Fresnel lens, a heat sink accommodating the light-diffusion member, the backlight and the Fresnel lens, and a mirror that forms a virtual image corresponding to an image displayed on the display screen of the liquid-crystal panel, in a target space, where a surface of the Fresnel lens facing the backlight is uneven.

What is claimed is: 
     
       1. A head-up display comprising:
 a liquid-crystal panel including a display screen; 
 a Fresnel lens which is on an opposite side of the liquid-crystal panel from the display screen; 
 a light-diffusion member between the liquid-crystal panel and the Fresnel lens; 
 a backlight emitting light toward the Fresnel lens; 
 a heat sink accommodating the light-diffusion member, the backlight and the Fresnel lens; and 
 a mirror that forms a virtual image corresponding to an image displayed on the display screen of the liquid-crystal panel, in a target space, 
 
       wherein
 a surface of the Fresnel lens facing the backlight is uneven. 
 
     
     
       2. The head-up display according to  claim 1 , wherein
 the light-diffusion member has a transmittance equal to or larger than 70%. 
 
     
     
       3. The head-up display according to  claim 1 , wherein
 the Fresnel lens is directly contacted to the heat sink. 
 
     
     
       4. The head-up display according to  claim 1 , wherein
 the heat sink has a plurality of plate-shaped fins protruding from an outer surface of the heat sink in a direction intersecting a direction in which the light-diffusion member and the Fresnel lens are arranged. 
 
     
     
       5. The head-up display according to  claim 1 , wherein
 the light-diffusion member is thinner than the Fresnel lens. 
 
     
     
       6. The head-up display according to  claim 1 , wherein
 the light-diffusion member has a thickness equal to or smaller than 300 μm. 
 
     
     
       7. The head-up display according to  claim 1 , wherein
 the light-diffusion member includes a plurality of fine particles; and 
 an average particle size of the plurality of fine particles is equal to or smaller than 20 μm. 
 
     
     
       8. The head-up display according to  claim 1 , wherein
 light emitted from the backlight diverges in a direction toward the Fresnel lens. 
 
     
     
       9. The head-up display according to  claim 1 , wherein
 light emitted from the backlight converges in a direction toward the Fresnel lens. 
 
     
     
       10. The head-up display according to  claim 1 , wherein
 the light-diffusion member includes the light-diffusion structure; and 
 the light-diffusion structure is provided to a surface of the light-diffusion member facing the liquid-crystal panel. 
 
     
     
       11. The head-up display according to  claim 1 , wherein
 the light-diffusion member includes the light-diffusion structure; and 
 the light-diffusion structure is provided to a surface of the light-diffusion member facing the Fresnel lens. 
 
     
     
       12. The head-up display according to  claim 1 , wherein
 the light-diffusion member includes the light-diffusion structure; and 
 the light-diffusion structure is provided to each of a surface of the light-diffusion member facing the liquid-crystal panel and a surface of the light-diffusion member facing the Fresnel lens. 
 
     
     
       13. The head-up display according to  claim 1 , wherein
 the light-diffusion member is made of glass or resin. 
 
     
     
       14. The head-up display according to  claim 1 , wherein
 the heat sink is made of aluminum. 
 
     
     
       15. The head-up display according to  claim 1 , wherein
 the heat sink includes a body part having a hollow rectangular prism shape. 
 
     
     
       16. The head-up display according to  claim 1 , wherein
 the backlight includes light emitting diodes or laser diodes. 
 
     
     
       17. The head-up display according to  claim 1 , wherein
 the Fresnel lens is made of glass or resin. 
 
     
     
       18. The head-up display according to  claim 1 , wherein
 the light-diffusion member is made of resin in which fine particles are dispersed. 
 
     
     
       19. An image projection system comprising:
 a liquid-crystal panel including a display screen; 
 a Fresnel lens which is on an opposite side of the liquid-crystal panel from the display screen; 
 a light-diffusion structure between the liquid-crystal panel and the Fresnel lens; 
 a backlight emitting light toward the Fresnel lens; and 
 a main part accommodating the light-diffusion structure and the Fresnel lens, wherein 
 a surface of the Fresnel lens facing the backlight is uneven. 
 
     
     
       20. A head-up display, comprising:
 the image projection system according to  claim 19 ; and 
 a mirror that forms a virtual image corresponding to an image displayed on the display screen of the liquid-crystal panel, in a target space.